1. Field of the Invention
The present invention relates to a machining system provided with a robot which transfers a workpiece to a processing machine.
2. Description of the Related Art
Conventionally, a workpiece is transferred to a processing machine by a robot and is machined by a machining tool of the processing machine. In particular, in a machining operation, such as burring, polishing, or grinding, there are cases where the workpiece held by a hand of a robot is machined by a machining tool which is rotating while pressing the workpiece against the machining tool. In this connection, Japanese Patent Application Laid-Open No. 2008-142810 discloses a method for adjusting the movement of an arm portion of a robot so as to obtain an appropriate magnitude of force acting between the workpiece and the machining tool during the machining operation. Furthermore, the aforementioned Patent Application Laid-Open No. 2008-142810 discloses a force sensor attached to the arm portion of the robot to measure the force as well.
When the workpiece is pressed against the machining tool of the processing machine by the robot, the machining tool may be deteriorated (e.g., wearing of the blade or abrasive) depending on the material of the workpiece or machining time, etc. In this case, it is necessary to maintain the quality of the machined workpiece by modifying the machining conditions depending on the degree of deterioration of the machining tool. For example, it is necessary to perform machining while complexly controlling the rotational speed of the machining tool and the movement speed of the workpiece.
However, in the apparatus disclosed in the Japanese Patent Application Laid-Open No. 2008-142810, only the force acting between the workpiece and the machining tool is adjusted while the workpiece is pressed against the machining tool of the processing machine by the robot. In other words, in the Japanese Patent Application Laid-Open No. 2008-142810, the rotational speed of the machining tool and the movement speed of the workpiece are not modified depending on the degree of deterioration of the machining tool. Consequently, it is difficult to maintain the machining quality of the workpiece when the machining tool is deteriorated during the machining operation.